dubesor

Hi everyone!

I would like to change the gearing on my road bike to have a "granny gear" for a tour I'm doing that's coming up really soon. I've done the same tour before without a granny gear, but just barely with the super long hills extremely tough to do. I'm not as trained up this year so really need to have that option.

Can you guys let me know if it's possible to upgrade the existing gearing to have a granny gear and exactly what parts I would need?

What I have now is a Shimano "Golden Arrow" 105 groupset from the 1980s - as shown here.

Right now, the bike is 12 speeds - 2 front cogs x 6 rear cogs. I 'm attaching some photos, see below ...

dedhed

I believe you would need a 'triplizer" inner ring and a longer BB

https://www.peterwhitecycles.com/chainrings.php

revcp 

Or IRD. https://store.interlocracing.com/cotrch.html

Among the problems you will run into, the wider bb spindle will shift the rings out and mess up your chain line. Also, the tripleizer will be replacing your present inner ring, and you would need to purchase a 74 BCD granny (and I'm assuming your present crank is 110 BCD, which is not really a safe assumption). Lastly, the new rings will likely be 9 speed, while your large ring will be six speed, meaning the wider chain that will be necessary to accommodate the 6 speed ring will be a bit sloppy on the 9 speed rings. It's tough.

clubman 

It would be easy to source a wide range 13 - 32 freewheel (IRD) and swap the RD and chain for some useful touring gears

bikemig 

+ 1. This is the easiest and most cost effective solution. You need a wide ranging freewheel, a long cage rear derailleur and a new chain.

We could use some more pictures of the drive side to see the crank and rear derailleur.

Still the suggested solution will work and is likely your most cost effective option. The IRD freewheel runs $60, a KMC 6-7 speed chain runs around $7 on Amazon, and a Shimano Claris rear derailleur that can handle the 32 tooth freewheel run around $29 on Amazon. You can find used stuff that will do the job for less money but this is available right now if you need to order it to get your bike set up.

rccardr 

Depends on how much change you want. Current crankset is 130 BCD, so smallest inner ring you can run is a 38. I'd suggest looking for a mid 80's Deore or Shimano 6206 triple crankset, which is 110/74 BCD, so you can run it as a double or triple with as small as a 26 inner ring. You might be able to get by with your current BB if you run a double, but will likely need a wider one if you go the triple route.

Out back, pretty sure that RD is rated at a maximum cog size of 26. You might be able to stretch that to 28 with a little fiddling with chain length, B screw setting (if that RD even has one) and rear axle placement in the dropouts, but for more than that you'll need a different RD. Again, mid-80's Deore will do the trick just fine for both the additional wrap needed for thr front ring change and a cog size up to 34.

None of this is cheap. Assuming you have the tools and know-how and are able to secure the appropriate bits at reasonable prices, it's about a $200 investment.

Goofball

I went to 2 bike shops to get an ird freewheel and was given 2 nutty reasons why they couldn't order it for me. I have the shimano megarange 14-34, works well but the jump from 24 to 34 is driving me crazy(er) 😵

canklecat

Yeah, the jump from 24 to 32 on the Shimano Megarange is horrible. I ditched that freewheel ASAP from my comfort/errand bike. It already has a 28/38/48 triple so I replaced the original 7-speed freewheel with a 14-28 from SunRace. Much smoother transitions, and the 28 is plenty for that bike, even loaded down. The bike weighs about 35 lbs and I haul up to 50 lbs of groceries and livestock supplies. No problems.

Any SunRace or Shimano freewheel in the 14-28 range should do the trick and cost under $20.

Replace the inner chainring with a Vuelta 38T or 39T (the smallest they have for 130 bcd) and you might not need a triple.

Depends on how much you plan to haul on the bike. I'm accustomed to hauling up to 50 lbs on my heavy errand bike, but my longest rides are around 20 miles. Usually much shorter, but with a steep climb. For a proper bike tour, a lighter bike and lighter load of minimalist gear would be fine on my road bikes. I'm not a strong climber but I could get by with the 50/39 chainrings and 13-25, 13-26 or 13-28 freewheels I already have.

seypat

If you decide to change cranks to a 110/74, Shimano Deore or FC-6206 are good options. Sugino and Sakae both made 110/74 cranks that came on bikes as doubles. No third ring but the holes are there for one.

bikemig 

I like shimano freewheels and that's disappointing about IRD inventory. The problem with Shimano freewheels is that the mega freewheel, 14-34, has a huge jump from 24 to 34. That may work for the OP but that is a big jump. Also these are 7 speeds and the OP has 6. That's not a big deal since both are used on 126 mm rear wheels but sometimes when going from 6 to 7 you get a big of chain rub and you have to put a 1 mm spacer to deal with that.

Lascauxcaveman 

I hated that ugly thing too. Couldn't wait to get rid of it. Worst $15 I ever spent.

79pmooney

There are a lot of old Sugino, Sakae Royal (SR) and Specialized (probably built by one of the former) triple cranksets out there, on-line, in boxes of used stuff at bike shops and coop, etc. 110/74. $50 should get you a good one. A Shimano 117 BB will work fine (~$30 new at a shop). A SunRace or Shimano 13 or 14-28 freewheel and a rear derailleur that can handle the chain take-up. I do not know how well you can get these items to work with index shifters as I have not played the index game yet.

If modern indexing is something you can go without, this does not have to be prohibitively expensive.

Ben

pastorbobnlnh 

I'm going to throw an uncertain curve ball at this conversation:

I believe looking at the second picture of the back view of the rear sprockets, the OP might have a UniGlide Cassette and not a freewheel. Noticed the "twisted teeth" (so Shimano UniGlide and not a Suntour, Regina, or Atom, etc. freewheel). But also notice there does not appear to be any room for a removal tool for a freewheel (now I could be wrong on this because the angle of the photo is not great).

If the OP is dealing with a freehub and a UG cassette, our guidance for lower gearing needs to be adapted a bit.

What do others think about the 2nd picture? Is there enough of a gap to slip a removal tool in there or are we talking two chain whips and possibly modifying a HG cassette?

rccardr 

Good point, Bob.
Appears to be an FH-105 rear hub, which is a 126OLD freehub. Makes fitting rear cogs easier to customize (either find the UG cogs you want or slightly modify HG cogs).
Still, that part aside, to get where the OP wants to go will require some derailleur and/or crank replacement.

seypat

When I looked at the 105 golden arrow group on Velobase, the rear hub is listed as a cassette.

VeloBase.com - View Group

seypat

Counting the teeth in the picture, it appears the big cog is either a 26 or a 28. If that's the case, maybe only change the crank to 110 or 110/74 with a compact setup. He might get lucky and can use the same BB spindle. Velobase says that crank takes a 116mm spindle. Find a 110 or 110/74 crank that takes a 116mm. Simple swap. Or find a crank. There are plenty of cheap BB spindles out there.

seypat

Here's Sheldon's chart for some reference:

https://www.sheldonbrown.com/bbsize.html

revcp 

Uniglide is cassette, but the freewheel hub won't accommodate a hyperglide cassette.

clubman 

Darn missed that Uniglide but if you have a good hyperglide body, it's a five minute job to swap it in. Except the first generation Uni iirc.

rccardr 

Hub body can't be swappedwith a later HG one as they are an entirely different design.
However, HG cogs can be easily modified ro fit a UG freehub by filing/Dremeling the small slot slightly larger.
Takes maybe 40 seconds per cog. Very easily done.

cannonride15

Or you can get one of these Corsa Vuelta triple cranksets for less than a used vintage set; as I did. https://www.amazon.com/gp/r.html?C=1...3920290_dpLink

terrymorse 

Is there any reason why swapping out this bike's cranks for a super compact crankset wouldn't work?

IRD makes a crankset with 46-30 chainrings, and it fits on a square taper bottom bracket spindle (which this bike seems to have).

IRD Defiant Super Compact Crankset


FSA also makes the Tempo Adventure crankset, with 46-36 rings and a square taper:

FSA Tempo Adventure Crankset

Jeff Wills

I agree that it is a Uniglide cassette. Changing the ratios on the rear is a lot tougher than simply swapping a freewheel or changing a cassette. It's certainly possible to adapt Hyperglide cogs to fit, but it takes someone willing to get in and Dremel on the cogs' splines.

IMO, the best bet is a triple crankset. The Shimano 600 triple crank is one of the best of the era (and, also IMO, any era) but they can be hard to find:
VeloBase.com - Component: Shimano FC-6206 Biopace, 600EX (Triple version of FC-6207)
It accepts 110mm/74mm BCD chainrings so it's possible to install a 24-tooth granny. That's a low enough granny gear for most people.

Here's one on Ebay:
https://www.ebay.com/itm/Vintage-Shi...8/254243285892

Cycle Tourist

Short answer, yes. It won't make a sport bike into a LHT but you can do it. Some triples push all the gears out from the BB rather then put a granny to your inboard side too close to the frame. Your present spindle may work and that derailleur may have the range to get all three gears or one or both may need to be replaced. If you go for a very low granny, you will probably need a mid or long rd. If you don't go too low you'll find it more useful, easier to shift and use. Stay with your 6 speed. A 7 speed freewheel will probably fit but not be as easy to shift and you may need a new chain....so, yes!

pastorbobnlnh 

I believe we've reached the consensus our OP @dubesor is dealing with a version of the Shimano UniGlide cassette as opposed to a freewheel.

As has been mentioned, it is easy to adapt and modify a current HyperGlide compatible cassette to work with an old UG freehub body. This is especially useful on the original UG body which cannot be swapped for a new HG body. It is suspected this body is one of the non-compatible models. However, it is difficult to be certain by just the pictures.

If dubesor is up to it, my preference is to work with a 9 speed HG cassette. A 9 speed opens up the possibility of moving from a 6 speed to a 7 speed by utilizing the 9 speed spacers. Of course friction shifting will need to be used. The cassette needs to be one where all the sprockets are either held together by a long screw or rivet.

1. Assuming the UG cassette has been removed, clean and keep the 13T threaded UG sprocket and clean and keep the original UG spacers.
2. Remove the screw or grind off the head of the rivet. Separate the sprockets and spacers.
3. Select the 5 or 6 sprockets for the new hybrid cassette.
4. Using a Dremel or other small grinder, shorten the long tab to the size of the small tabs. Check to make certain the HG sprockets fit on the UG freehub body.
5. Paying attention to line up all the modified tabs in the same freehub grove, add sprockets and spacers, first trying to 9 speed spacers to make a HG-UG hybrid 7 speed cassette. Secure with the original threaded UG 13T.
6. If all the threads of the13T do not engage on the body, remove and remount with the original UG spacers for a HG-UG hybrid 6 speed cassette.
7. My preference is to use a 8 or 9 speed SRAM or KMC chain with a quick link.

And Bob's your Freewheel Medic!